Tub and top construction for dishwashers



June 9, E953A H. o. SMITH TUB ANDv To? CONSTRUCTION FOR DIsHwAsHERs 4sheets-shea 1 Filed Nov. 8, 1950 f 1 w 1 .l|| Jv. A "Y T--\ v "A f VII..j J 7 8 6 nventor Alfamrolal 0. Smith @im Wag@ Gttomegs June 9, 1953 H.o. sMrrH TUB AND TOP CONSTRUCTION FOR DISHWASHERS Filed Nov. 8, 195o .4Sheets-Sheet 2 :inventor l. Harold Smblz- Bg l Gttornegs `Flauta@ 9,1953 H. o. SMITH Y 2,641,380

TUB AND ToP CONSTRUCTION FOR nrsrmAsHERs I Filed Nov. 8, 195o 4slm'cg-shan-l s"r T l A Impex-nor zo 28 HwroldSmilz 53 Bu v June 9, 1953H. o. sMrrH.

TUB AND TOP CONSTRUCTION FOR DI'SHWASHERS Filed Nov. 8. 195i 4Sheets-Sheet 4 wrolal 0. Smith Patented June 9, 1 953 TUB AND TOPCONSTRUCTION FOR DISHWASHERS Harold 0. Smith, Salem, Ohio, assignor toMullins Manufacturing Corporation, Salem, Ohio, a corporation of NewYork Application November 8, 19570, Serial No. 194,669

s claims. (c1. 22040) The invention relates to dishwashers, and moreparticularly to a dishwasher tub and top construction in which the tuband top are supported separately on the dishwasher cabinet with a jointtherebetween through which the tub interior may be vented withoutleakage of washing liquid which may flow or splash upward along the tubside walls during dishwasher operation.

l Increasing numbers of power dishwashers are being installed and usedin household kitchens either as individual dishwasher units or as partsof sink-dishwasher units. Such dishwasher units normally include acabinet and a counter top which preferably are arranged to be installedadjacent to and in continuation of kitchen base cabinets or sinkcabinets, and the counter or sink tops thereof.

The counter top for a, dishwasher cabinet, either separately or combinedwith a sink, should be arranged to be aligned with the counter or sinktops of adjacent base or sink cabinets.

Preferably, the dishwasher counter top member is formed of sheet metalcoated with vitreous enamel, and if the dishwasher is a combinationsink-dishwasher unit the enamel coated sheet metal top thereofintegrally includes a sink bowl or basin.

For many reasons it is desirable to gain access to the dishwasher tubthrough an opening in the counter top, rather than through the front ofthe dishwasher cabinet. Such access opening, located above the upper endof the tub and formed by a downwardly extending flange, is closed by alid forming a part of the counter top; and it is desirable to provide aliquid-tight seal for the lid when closed so as to prevent leakage ofwashing liquids around the lid when the dishwasher is in operation, andlikewise to prevent liquids, food or other materials being processed onthe counter top from entering the interior of the dishwasher around theclosed lid.

Furthermore, the dishwasher tub also preferably is formed as a deepdrawn sheet metal member coated with vitreous enamel so that the samemay be kept in a sanitary condition at all times.

Also, it is desirable to mount the enamel coated sheet metal tub andtopv members separately in or on the dishwasher cabinet to permit readyrepair or replacement of either of these members, or of other parts ofthe dishwasher. Accordingly, in order to satisfy the foregoingconditions, it is necessary to provide a joint between the upper endofthe tub and the tub access opening in the dishwasher counter top. Thisjoint, however, must be capable on the one hand of permitting venting ofthe interior of the tub when the lid is closed, and on the other hand ofpreventing leakage or overow of washing liquids splashing or owingupward within the tub along the tub side walls during dishwasheroperation.

The venting of the dishwasher tub is necessary so as to prevent pressurefrom building up within the tub upon closing the lid which would resistready closure and sealing of the lid, and to prevent bulging of the lidor other dishwasher parts when the lid is closed, incident to expansionof air within the tub heated by hot water introduced into the tub afterthe lid is closed for washing and rinsing.

Thus, a diilicult problem is presented of providing a joint between thedishwasher tub and top satisfying all of the foregoing conditions. Thisproblem is further complicated by the necessity of keeping any overlapof the upper end of the tub side walls and the downturnedaccessopening-forming-flange on the counter top at a minimum, so as toretain a maximum amount of work space within the dishwasher tub.

The provision of vitreous. enamel coatings on the sheet metal tub andtop members further complicates the problem. It is not possible inproduction to maintain close tolerances in the tub side wall and topaccess opening angesizes when these members are formed of vitreousenamel coated sheet metal. Also, the burning or firing steps used inproviding the vitreous enamel coating on the sheet metal tub and topmembers may cause warpage of these members, with the result thatthe tubside walls or access openingv flange, or both, may be slightlyout-of-round when received for assembly with the dishwasher cabinet.

Finally, proper dishwashing action is dependent in part upondischarging, jetting, or otherwise moving or ilowing washingliquidswithin the tub against dishes therein with considerable forcesuch that the liquids striking the tub side walls will splash orotherwise flow in all directions along the tub side walls, includingupward. Upward movement of washing liquids along the tub side walls nearthe top thereof may overflow from the tu'b member and drip into thesurrounding cabinetfunless such movement or now is restrained or turnedin a direction to avoid overflow.

Accordingly, it is a primary object of the present invention to providea new enamel coated sheet metal dishwasher -tub and top joint con- Istruction.

Furthermore, it is an object of the present invention to provide a newjoint construction between the upper end of the side walls of a sheetmetal dishwasher tub and a downturned flange forming the tub accessopening in the dishwasher top member which permits venting of theinterior of' the tub when the lid for the access opening is closed andsealed in a leakproof manner.

Also, it is an object of the present invention to provide a newdishwasher tub and top oonstrnc` tion having a vented joint therebetween'which prevents water, splashing or flowing upward of the tub side wallsduring dishwasher operation, from overflowing at the top of the tub.

Likewise, it is an object of the present invention to provide a ventedbut liquid leakageinhibiting joint construction for dishwasher tub andtop members in which dimensional instability as to size and roundness ofthe tub and top members, incident to' enamelingthe parts, does notprevent the proper formation of such a joint therebetween.

Finally, it is an object of thev present invention to provi-dey a newdishwasher tub and top joint construction incorporating the foregoingdesiderata, which may be fabricated readily, which satisfactorilysolves` the complicated described problems ,and which obtains` theforegoing advantages in a Simple, effective, and inox'- pensive manner.

These and other objects and advantages apparent to those skilled in theart froml the following description and claims may be obtained, thestated results achieved, and the described difficulties overcome, bytheimprovements, elements, combinations, sub-combinations, arrangements,constructions, devices and parts which comprise the present invention,the nature of which is set forth in the following general statement, apreferred embodiment of which--illustrative of the best mode whichapplicant has contemplated applying the principles-s set forth in thefollowingY descriptionl and' shown in the drawings' and which areparticularly anddistinctly pointed out and set forth in the appendedclaims'forming part hereof.

The nature ofv the discoveries and improvements dishwasher tub and topconstruction may be stated` general terms as preferably including in adishwasher, a cabinet, a preferably v vitreous enamel coated sheet metaltub member having preferably cylindrical side walls mounted within thecabinet, a preferably vitreous enamel coated sheet metal counter topmember mounted on the` cabinet having a downturnedA annular flangeforming a tub access openingv in the-top member, a lid for the opening,means for sealing the lid when closed in a leakproof mannen, said flangebeing preferably cylindrical: and terminating at its lower endpreferably in a slightly outturnedcurved lip, said flange beingtelescoped within the upper end of the tub side walls-With; a clearancespace between the tub side walls and lip, an annular, inwardly-directedbead formed in the tub side walls immediately above said lip"l said tubside walls terminating` in an outturned and. then preferably downturnedange with an annular, preferably right angled, corner between the tubside walls and said outturned flange, and the normal outer diameter ofsaid lip being equal to or slightly larger than the normal. insidediameter of said bead.

`By way of example, a preferred embodiment of the improved dishwashertub and top` construction is illustrated in the accompanying drawingsforming part hereof, wherein:

Figure l is a front elevation, with parts broken away and in section, ofa dishwasher unit provided with the improved construction;

Fig. 2 is, a top plan View,l with parts broken away and in section, ofthe dishwasher shown in Fig. 1;

Fig. 3 is an enlarged fragmentary section Athrough the improveddishwasher tub and top joint; Fig. 4 is a fragmentary section taken onthe line 4-4, Figv 3',

Fig. 5` is a diagrammatic view illustrating the manner inwlnch the topmay be assembled with the tub in the improved dishwasher construction;

Fig, G is a front elevation, similar to Fig. ll, illustrating theimproved construction in a combined dishwasher and sink unit; and

Fig. 7 is a top plan View of the unit shown in Fig. 6.

Similar numerals refer to similar parts throughout the various gures ofthe drawings.

An individual dishwasher unit made in accoi-dance with the presentinvention is illustrated in Figs. 1 and 2, the dishwasher tub memberbeing generally indicated atA I, the dishwasher top member at 2, and thedishwasher cabinet at 3. The cabinet `3 may be constructed inthe usualmanner of sheet metal with painted surfaces' comprising a base portiond", sidewalls 5l terminating in front corner portions 8, an upper panelportion 1, and a door-'8.

Theftop member 2 preferably is provided with vitreous enamel surfacesand, as illustrated, may be formed from sheet metal witha vitreousenamel coating thereon. The top member 2 includes a splash hack portion9, a top rim portion lilterminating in a depending or down# turnedflange H which surrounds the front and sides of the top member andmerges with the side surfaces f2 of the splash back portion 9. Thedownturned top member iiange ii preferably terminates in an in-turnedflange i3' resting on a gasket or other cushioning or seating member Hi,which in turn rests upon an inturned flange ILE at the topedges of theyfront and-side walls of the cabinet 3'. Thus, thel top member 2 ismounted on and' supported by the vcabinet 3'.

An opening. for gaining access to the dishwasher tub i is formed in thetcp member 2- by a downturned flange portion I6v which may be somewhatrectangular` in configuration when viewed from the top (Fig 2)y withrounded corners Il; The flange portion it terminates in an inturnedshoulder or ledge i8, which terminates inwardly in a preferablycylindrical downturned tub adjoining flange lug. The bottoni open end ofthe flange i9 preferably is formed with a slightly outturned, curved lipindicated at 2-0'. Thusr the tub access opening is formed by the flangeportions I6 and lil, and this opening may be closed by a lid member 2lpreferably formed of vitreous enamel coated sheet metal and hinged at 22to the top member 2. The lid 2| is shaped to have the same configurationas the shape of they flange portion lo and-j corners il, and is providedwith4 a gasket 2.3 which tightly' seats onthe shouldered ledge it when;the lid is closed, thus forming a liquid-ti-ght.y seal for the lid so asto preventV leakage of washing' liquids around the lid when thedishwasher ist in; operation. rfhe. seal also prevents liquids, food,or. other materials processed on top of. the lid, from entering theinterior of, the. dishwasher whenthe lid is closed.

2' The upper surface of the lid 2I is preferably at and lies preferablyin the sameplane as the top surface of the rim portion I0, so as topresent a counter surface for use as a work space for the preparation offoods and other materials in the kitchen; and this top counter surfacemay have the same height as and be Vformed as a continuation of adjacentkitchen base cabinets having similar counter or work surfaces.Preferably, the lid 2,I is provided centrally, .with a glass window 24through which the operation of the dishwasher may be observed.

Although the top member 2 has been shown and `described as being formedintegrally in one piece of vitreous enamel coated sheet metal, it is tobe understood that the same may be made as a cast vitreous enamel coatedproduct, or as a porcelain china member. Alternatively, it can be formedof stainless steel or Monel metal.

A preferably sheet metal tub support member 25 is mounted within thecabinet 3 near the top of the cabinet front and side walls, and thissupport member is formed inwardly and upwardly with a preferablycylindrical ring portion 26 (Fig. 3).

'I'he tub member I is formed as a deep drawn vitreous enamel coatedsheet metal member having a sump portion 21 and a cylindrical side wall28 terminating at its upper end in an outturned rim ange 29 formedintegrally as a part of a depending annular flange 30. The tub fiange 30is telescoped over the support member ring portion 26, and the members26 and 3Ilmay be joined by nuts and bolts 3| whereby the tub member I ismounted within the cabinet -3 on the support member 25. In accordancewith the present invention, the annular corner 32 between the tub sidewall 28 and rim 29 is formed on as small a radius as possible consistentwith good enameling practice to provide as sharp a right angle cornerbetween members 28 and 29 asposvsible for a purpose to be hereinafterdescribed.

When the tub and top members I and 2r are assembled with and supportedby the cabinet 3, the cylindrical tub adjoining ange I9 of the topmember2 is telescoped within the upper end of the cylindrical tub side wall 28with a clearance space indicated at 33 in Fig. 3 between tub side wall28 and outturned, curved lip 20 at the lower end of flange I9. The sidewall 28 of the tub member I is provided with an annular inwardlydirected bead 34 immediately above the lip 20, and the normal outerdiameter of the lip 20 in accordance with the present invention is equalto or slightly larger than the normal inside diameter of said bead 34,as shown in Figs. 3 and 4. y y

When thetub and top members I and'2 are assembled as shown, an annularpassage 35l is formed between flange I9 and the upper end of the tubside wall 28 communicating through clearance space 33 with the interiorof the tub and also with the interior of the cabinet 3 surrounding thetub. This passage provides a vent for the tub, preventing pressure from'building up within the tub I upon closing the lid 2|, which pressurewould resist ready closure and 'sealing of the lid. TheV venting alsoprevents bulging of the lid or tub walls when the lid is closed, as aresult of expansion of air within` the tub when heated by hot waterintroduced into the tub after the lid is closed for carrying out thedishwashing operations. i

When the dishwasher is infuse,vwashing or rinsing liquids aredischarged, -fjetted,"or other- 6. wise moved with lconsiderableiorce'within 'the tub against dishes therein, and these liquids strikethe tub side wall 28 and splash or otherwise iiow in all directionsalong the tub side wall. Any upward movement of such washing liquidsflowing on the tub side wall near to thetop must pass through theclearance space 33 whence the direction of flow is immediately turnedinward by the annular bead 34. This inward turning of the flow ofliquid, if still flowing with any appreciable force, will strike theexterior surface of the top flange I9, and its force will be spentbefore any liquid can travel upward to the top of the flange I9. Thespent liquids which may .enter through clearance space 33 then -dripdownward along the exterior surface of the ange I9 to lip 28 and thenceinto the tub I. v

If any upwardly flowing liquids should continue tohug the tub side wall28 by passing around bead 34, they must continue to flow'verticallyupward alongthe tub f side wall por. tion 36 a substantial distancebefore reaching the corner 32, and the force of such flow will be spentbefore the liquids can reach the corner 32. As indicated, the corner 32is made as sharp a right angular corner as possible to inhibit anytendency of liquids to iiow around the corner 32 and overow the tub.

Thus, the particular cooperative construction, arrangement, and relativelocation of the tub ad-4 joining flange I9 of the top member 2, its lip20, the tub side wall 28, bead 34, wall portion 36, and sharp corner 32,provide a vent for the tub and yet prevent overflow of splashed washingliquids through the vent opening or passage 33-35. l

Unfortunately, the characteristics of vitreous enamel coated productsprevent close tolerances from being maintained in the size and concen-ftricity of the cylindrical tub wall 28, top ange I9 and lip 20, thusrequiring the clearance space 33 to be substantial. The tub wall 28,when iired to form the vitreous-enamel coating, may warp out-of-roundand the enamel on the lip edge 20 may fuse in such manner as to presenta slightly irregular edge. Similarly, the cylindrical ange wall I9 maywarp out-of-round when fus'- ing the enamel coating, or on ring thepart, if made ofporcelain china.

Ifthe outer diameter ofthe lip 20 on the bottom end of ange I9 could inproduction be made to'closely t the internal diameter of the tubwallf28, the lip 20,would stop any upward flow of washing liquids on thetub wall'28, ytherebyl eliminating the necessity of providing the bead34. However, for `the reasons stated above, the clearance space 33 mustbe substantial, and thus a substantial annular channel is present at theclearance space 33 through which upwardly splashed liquids may flow. Inorder to turn these liquids and prevent 'overflow of the tub, theprojection of the bead 34 must rlikewise be substantial Whilemaintaining the clearance space 33 at a minimum.

`These requirements are satisfied by the present invention by therelative dimensions of the inner diameter of bead y34 and outer diameterof lip 20 which, as described, are either the same or the lip diameterslightly greater than the bead diameter. This arrangement in turnApresents an assembly problem whichis overcome in the manner illustrateddiagrammatically in Fig. 5, in which the arrows 3'1 represent the insidediameter of the bead 34, while the arrows y38 represent the outsideprojected diameter of the lip 2i) taken at right angles to thediameter3'l, with the'bottom'surface of the lip"'20 or the:

bottom'cnd of the flange wall l5. tilted out of. parallelism with aplane passing through. the inside diameter of bead 3,4.

In other words, if, in assembling the parts, the tubV is located withits axis directly vertical and the top member is tiltedout-of-horizontal, the circular edge of lip 20 presents an ellipticalprofjection when viewed in plan along the axis of the tub, and there arethen only twopoints on the lip 20, at the extreme endsof diameter 3T,which will contact the bead 34 when. it is attempted to telescope thelip 26) past the bead 31H20 the assembled position shown in Fig. 3. Ifthe outer diameter of lip 20 is slightly larger than the internaldiameter of the bead 3A, the lip 20 may still be telescoped past thebead because there is suiiicient springiness or resilience in the sheetmetal ange wall I9 to permit it tosprng outo-fround, so that the twocontacting points at the end of diameter 3l on the outer edge of lip 2@will snap past the bead 34.

The sharp angular corner 32 at the top of the tub,` in addition toassisting in preventing tub overflow, also substantially stiflens theupper end of the tub against warping out-of-round during the enamelingoperation, and aids the tub side walls in maintaining proper shape aslip 20 is telescoped past bead 34.

Referring to Figs. 6 and 7, the improved construction is there shownincorporated in a com bined sink-dishwasher unit generally indicated at39, in which the dishwasher portion 4l]A at the right end of the unit issubstantiallyidentical in construction with the dishwasher unitillustrated in Figs. 1 through 5. However, the cabinet generallyindicated at 4I is wider and is provided with twodoors 42 and 43, and asink M is incorporated integrally in the top member 45. In otherrespects, the tub member 46 is mounted within the cabinet 4i andassociated with the top 45 in the same manner as previously described..

Accordingly, the present invention provides an improved dishwasher tuband top member construction in which the tub and top members areseparately supported on the dishwasher cabinet so as to permit readyreplacement or repair of either of the parts; provides a joint betweenthe tub and top members through which the tub may be vented when the tublid is closed; provides a vented joint which prevents the overow ofsplashed washing liquids from the tub` through the vent opening orpassage; provides a construction which incorporates the foregoingarrangements notwithstanding the inability to maintain close tolerancesin the manufacture OI the dishwasher tub and top from vitreous enamelcoated sheet metal; and provides a construction which may be fabricatedreadily and satisfies the complicated problems presented in a simple,ef-A fective, and inexpensive manner.

In the foregoing description, certain terms have been used for brevity,clearness, and understanding; but no unnecessary limitations `are to beimplied therefrom beyond the requirements of the prior art, because suchterms are used for descriptive purposes herein and not for the purgposeof limitation, and are intended to be broadly construed.

Moreover, the embodiments of the improved construction illustrated anddescribed are by way of example, and the scope of the present inventionis not limited to the exact details of construction of the variousparts.

Having now described the features, discoveries, and principles of theinvention, the manufacture and assembly ci preferred embodimentsthereof, and the advantageous new and useful resuits obtained thereby;the new and useiul im movements. discoveries, elements, combinations,

sub-combinations, arrangements, constructions..

devices, and Darts, and reasonable mechanical equivalents thereofobvious to those skilled in the art. are, setforth in the: appendedclaims.

I claim:

1. In dishwasher construction, a sheet. metal tub. member havingupwardly projecting side walls, there being an inwardly projecting beadformed around the tub side-walls spaced below the top edges thereof, acounter top member for the tub having a downturned tub adjoining ange,telescopedwithin the tub side walls terminating at its lower end in a.flared lip located immcdh ately below saidbead' and forming an accessopening for the tub member, there being a clearancel space between the.lip and tub side walls providing a tub vent, and the outer perimetricdimension of said lip being'not less than the inner perimetric dimensionof said bead.

EL In dishwasher construction, a tub member ,f having an upwardlyprojecting, cylindrical side wall, there being an inwardly projectingannular bead formed around the tub side wall spaced below the top edgethereof, a counter top member for the tub having a downturned,cylindrical, tub adjoining flange telescoped within the tub side wallterminating at its lower end in af flared lip located immediately belowsaid bead and formingan access opening for the tub member, one oi' saidmembers being formed of shoel metal, there being a clearancespacebetween the lip and tub side wall providing a tub vent, and theouter diameter oi'v said lip being at least equal to the inner diameterof said bead.

3. In dishwasher construction, a sheet met-al tub member having anupwardly projecting cylindrical side wall terminating in an outturnedange, there being an inwardly projecting bead formed around the tub sidewall spaced below said outturried flange, a counter top member for thetub having a downturned, cylindrical, tub adjoin# ing flange telescopedwithin the tub side wall terminating at its lower end in a flared liplocated immediately below said bead and forming an accessopening for thetub member, there being a clearance space between the lip and tub sidewall providing a, tub vent, and the outer diameter of said lip being atleast equal to the inner diameter orsaid bead.

4. In dishwasher construction, a vsheet metal tub member having anupwardly projecting cylin drical side wall. terminating .l in anoutturned flange formed as a part of l a downturned flange, a cabinet, esupport member mounted in the cabinet' engaged below and within saidout..- turned and downturned anges supporting the tub in the cabinet,there being an inwardly pro Jecting bead formed around the tub side wallspaced below said outturned danse, a counter top member for the tubsupported on the cabinet having a downturned cylindrical tub adjoiningflange telescoped within the tulo side wall ter.. minating at its lowerend in a Ilared lip located immediately below said bead and forming anac cess opening for the tub member, and there being a clearance spacebetween the lip and tub lside wall providing a tub vent.

5. In dishwasher construction, a sheet metal tub member having anupwardly projecting, cylin` drical side wall terminating lin anoutturned flange with a right angled, annular corner therebetween,y acabinet, means on the cabinet engage ing said flange supporting the tubin the cabinet, there being an inwardly projecting bead formed aroundthe tub side wall spaced below said outturned ange, a counter top memberfor the tub mounted on the cabinet having a downturned, cylindrical, tubadjoining ange telescoped within the tub side wall terminating at itslower end in a flared lip located immediately below said bead andforming an access opening for the tub mem ber, and there being aclearance space between the lip and tub side wall providing a tub vent.'

6. In dishwasher construction, a cabinet, a tub member having anupwardly projecting, cylindrical side wall mounted in the cabinet, therebeing an inwardly projecting bead formed around the tub side wall spacedbelow the top edge thereof, a counter top member mounted on the cabinetabove the tub, there being a downturned, cylindrical, tub adjoiningflange formed on the top member telescoped Within the tub side wallterminating at its lower end in a flared lip located immediatelyA belowsaid bead and forming an access opening for the tub member, said tub andtop members being provided with vitreous enamel coatings and one of themembers being formedwof sheet metal, and there being a clearance spacebetween the lip and tub side walls `providing a tub vent. 7. Indishwasher construction, a cabinet, a tub member having an upwardlyprojecting, cylindrical side wall mounted in the cabinet, there being aninwardly projecting bead formed around the tub side wall spaced belowthe top edge thereof, a counter top member mounted on the cabinet abovethe tub, there being a downturned, cylindrical, tub adjoining flangeformed on the top member telescoped within the tub side wall terminatingat its lower end in a ared lip located immediately below said bead andforming an access opening for the tub member, said tub and top membersbeing provided with vitreous enamel coatings and one of the membersbeing formed of sheet metal, there being a clearance space between thelip and tub side walls providing a tub vent, a lid for said accessopening, and means for sealing the lid in a leakproof manner whenclosed.

8. In dishwasher construction, a vitreous enamel coated sheet metal tubmember having an upwardly projecting cylindrical side wall terminatingin an outturned iiange, there being an inwardly projecting bead formedaround the tub side wall spaced below said outturned iiange, a vitreousenamel coated sheet metal counter top member for the tub having adownturned cylindrical tub adjoining -iiange telescoped Within the tubside wall terminating at its lower end in a flared lip locatedimmediately below said bead and k forming an access. opening for the tubmember, a cabinet, means supporting the tub member in the cabinet,separate means supporting the top mem ber on the cabinet, there being aclearance space between the lip and tub side wall providing a tub vent,and the outer diameter of said lip being at least equal to the innerdiameter of said bead.

HAROLD O. SMITH.

References Cited in the le of this patent UNITED STATES PATENTS NumberName Date 1,009,342 Jones Nov. 28, 1911 1,913,731 Skarstad June 13, 19332,275,705 Wagner Mar. 10, 1942 2,320,888 Reifenberg June 1, 19432,533,524 Snider Dec. 12, 1950

